The Impact of EL-NINO/Southern Oscillation (ENSO) on Fishery and Water Quality in Lake Kinneret (Israel)

Abstract

A correlation between fishery and extreme winter conditions in Lake Kinneret was indicated: po pulations of Bleak fishes were enhanced and those of Sarotherodon galilaeus (SG) declined. The aim of the present study is to confirm the relation of those correlations to EL-NINO/Southern Oscillation and its impact on Kinneret fishery. The study is based on long-term data records of the Kinneret Epilimnetic temperatures, water level increase, precipitation and air temperatures in the drainage basin, together with a record of EL NINO/Southern Oscillation (ENSO) events. Results suggest a confirmation of the impact of ENSO events on lake population size of Bleaks and SG. It is likely that the influence of ENSO on the two key fish species in the Lake is contradictory: enhancement of reproduction of the winter spawner Bleaks and reduction of population recruitment of the early summer spawner, Sarotherodon galilaeus. It is likely that winter extreme in Kinneret region is a consequence of ENSO event and therefore negatively affecting Kinneret water quality.